1. Field of the Invention
The present invention relates to an endoscope apparatus having switches arranged at respective positions thereof which allow the switches to be easily operated, such as a switch for controlling a curvature operation.
2. Related Art and Prior Art Statement
In recent years, an endoscope has widely been used in which an elongated inserting section is inserted into a body cavity, whereby internal organs within the body cavity are observed by an objective optical system which forms observing means provided at a forward end portion of the inserting section, or, as the occasion demands, a treatment instrument inserted into a treatment-instrument channel is used for executing various types of medical care treatments.
Further, an industrial endoscope has widely been utilized for observation, inspection and so on of internal wounds or flaws, corrosion or erosion or the like in a boiler, a gas turbine engine, piping of a chemical plant or the like, a body of a vehicle engine, and the like.
Generally, such an endoscope has a curvature mechanism for curving a curvature portion provided in the vicinity of the forward end portion of the inserting section so as to be capable of directing a viewing direction of an objective optical system at the forward end portion of the inserting section toward a direction of an objective part, wherein curvature operating means adjacent to the hand is operated, whereby the curvature portion can be remotely curved through the curvature mechanism.
In a case of a mechanical curvature mechanism, since the curvature mechanism must be driven by manual operation, a considerable capacity or ability is required during operation. For this reason, an endoscope has been known which is provided with an electromotion curvature drive mechanism in which electromotion drive means such as a motor or the like is arranged to electrically drive the curvature mechanism, and the curvature mechanism can be curved by a switch operation requiring almost no power or capacity at hand.
The endoscope having such electromotion curvature drive mechanism is combined with a curvature control device for controlling curvature of the endoscope, a light source device and the like, to form an endoscope apparatus, and has been utilized.
Furthermore, extraneous matter such as body fluid and the like frequently adhere to an outer surface of the objective optical system at the forward end portion of the inserting section, because the endoscope is inserted into a body so that an observing function is reduced. Water-feed and gas-feed mechanisms are arranged as a mechanism for removing the extraneous matters so as to remove or solve the above-discussed problem. A switch or a button adjacent to the hand is operated, whereby cleaning water is jetted toward the outer surface of the objective optical system, to wash away the extraneous matters and, subsequently, a switch or a button for feeding air is operated to blow away and remove droplets of the cleaning water remaining on the outer surface of the objective optical system, so that the outer surface of the objective optical system can be set to a clean condition having no extraneous matters.
Moreover, there is also an endoscope apparatus in which an endoscope is provided with suction means for sucking or drawing and discharging fluid such as body liquid or the like which interferes with observation within the body, and which can control suction operation by a suction switch or button.
There are many cases where the above-described operation switches executing various operations such as curving, air-feeding, water-feeding and suction, are arranged at the operating section connected to a proximal end of the inserting section. There is an endoscope apparatus in which such operations can be executed by a hand which grasps or grips the operation section.
An endoscope apparatus provided with an electromotion curvature drive mechanism, an arrangement in which control means for controlling an operating speed by operating time, a quantity of operation, an operational capacity and the like of the curvature operating switch is incorporated in a curvature control device has been disclosed in, for example, Japanese Patent Laid-Open No. HEI 1-317423, Japanese Patent Laid-Open No. SHO 58-78635, Japanese Patent Publication No. SHO 63-59329 and Japanese Patent Laid-Open No. SHO 58-69523.
A curvature operating switch at a rearward end portion of an operating section is also well-known. In this case, it is difficult to operate the curvature operating switch by a hand which grasps the operating section. Further, there is also a prior art device in which, even if the curvature operating switch can be operated by the hand grasping the operating section, it is difficult to execute operation of gas-feed/water-feed and suction.
Furthermore, in other prior art devices, a curvature switch executing curvature operation and a switch executing gas-feed/water-feed and suction are arranged respectively on surfaces adjacent to each other or adjoining each other. Accordingly, there is room for improvement of operation by the hand which grasps the operating section.
That is, in a case where various kinds of switches are operated under a condition where the operating section is grasped by one hand, at least two fingers are required such as, for example, a case of being grasped by the fifth finger and the third finger, or the like. In this case, fingers capable of being used in operation are three including the thumb, the first finger and the second finger, for example. Accordingly, if curvature operation is executed by the thumb, operations of gas-feed/water-feed and suction are executed by the first finger and the second finger, respectively.
If the curvature switch and the switch executing gas-feed/water-feed and suction are arranged respectively on the surfaces adjoining each other, in a case where the switch for executing gas-feed/water-feed and suction is operated, it is impossible to use the endoscope apparatus because the third finger and the second finger, for example, are grasped. For this reason, grasping capability is reduced so that operation becomes unsteady, increasing the burden in a case where grasping is executed by the fifth finger and the third finger which are used for grasping. Thus, the hand tends to become tired.
Moreover, also even in a case where curvature operation is executed, it is possible to curve the curvature portion in an optional curving direction out of a plurality of curving directions. However, in a case where curvature operation in a specific curving direction out of a plurality of curving directions is used most frequently, it is desirable that an operating position executing curvature operation into the specific curving direction is arranged at a location which lessens fatigue of the finger.
Generally, a curving operation curving upwardly is used most often. In the prior art, however, a position of the switch executing or performing the upward curvature operation is not arranged at a position closest to the thumb (in a case where the operating section is grasped). Accordingly, there is a problem that, if the curvature operation continues, the thumb tends to become tired.
In this manner, in the prior art, the arrangement of various switches at the operating section is not ideal, and there is room for improvement.
Further, there is a case where an electronic endoscope building therein image pickup means has been used in recent years. In this electronic endoscope, there is an arrangement which comprises a freeze switch for freezing an image displayed on a monitor to create a still picture, a release switch for indicating operation for recording an image by a recording device, or the like. Accordingly, if the number of switches increases, the number of operations of the switches increases. Thus, it is desirable to appropriately arrange the switches.